Which statement illustrates a cultural feedback loop affecting human evolution?

• A. Less hair leads to fewer pests, enabling fire and clothing
• B. Less hair leads to more pests, hindering clothing
• C. Genetic drift drives hair changes
• D. Natural selection eliminates hair

Answer: (A)

Culture and biology influence each other in a feedback loop that shapes how humans evolve. When hair is reduced, there are fewer habitats for ectoparasites, so pest pressure drops. That lower pest burden makes cultural tools like clothing and the use of fire more practical and beneficial for thermoregulation and protection. With culture providing new ways to cope with temperature and parasites, the selective environment shifts in ways that reinforce the biological trend toward less hair. This intertwining of biological change and cultural practice is what the statement captures. The other options describe processes that don’t involve this back-and-forth interaction between culture and biology, so they don’t illustrate a cultural feedback loop affecting evolution.